Felix ‘FX’ Lindner, Head of Recurity Labs


FX is the technical and research lead of Recurity Labs with over 25 years of experience in the computer industry, mostly consulting for large enterprise customers, and possesses a vast knowledge of computer sciences, telecommunications and software development. His background includes managing and participating in a variety of projects with a special emphasis on security planning, implementation, operation and testing, using advanced methods in diverse technical environments.

FX is well known in the IT security community and has presented his and Phenoelit’s security research on Black Hat Briefings, CanSecWest, PacSec, DEFCON, Chaos Communication Congress (CCC), MEITSEC and numerous other events. His research includes Cisco IOS, HP printers, SAP, RIM BlackBerry and much more. Felix holds a title as State-Certified Technical Assistant for Informatics and Information Technology as well as Certified Information Systems Security Professional (CISSP).

Felix has been awarded the 2017 Pwnie Award For Lifetime Achievement.

Operations Team


Nico and Florian represent the Operations team at Recurity Labs and serve as main point of contact. Apart from via their individual contacts, the Operations team can be reached via operations@recurity-labs.com.

Nico Lindner, CEO


In parallel to his studies of Applied Computer Science at FHTW Berlin, Nico started his professional career as an event technician and manager in the Audio/Video (AV) field. He quickly excelled and was promoted to deputy chief engineer in a highly respected venue and continued to fulfil this position until 2010, specializing in the management of events, while never losing hands-on grip of the ever-changing technical playground.

Having gathered over a decade of experience in this line of work, Nico was recruited to support the corporate management at Recurity Labs. Over the course of the years, he has taken on a major proportion of the management side at Recurity Labs and currently serves as its CEO.

Florian Grunert, Director Projects


Florian joined Recurity Labs in 2013, now representing the main project management contact at Recurity Labs. As “Director Projects” he is the responsible entity for the coordination, implementation, control and steering of the majority of Recurity Labs’ projects, while always remaining aligned with the strategy, commitments and goals of the involved organizations. Florian gathered broad experience handling complex and difficult projects from the initial request to long-term support, being a valued mediator both internally and externally.

Consulting Team

Michael Günther


As a Senior Security Consultant with the experience of countless projects for large financial industry and telecommunication customers, Michael complements the Recurity Labs team with his skills ranging from Threat Modeling of complex environments, analysis of process and procedure frameworks, to the execution of in-depth technical analyses. With close to three decades of expertise in the field of IT-security, Michael excels in identifying the crux of the matter.

Michael presented at DEFCON, Chaos Communication Congress, Chaos Communication Camp and Toorcon.

Carsten Wentzlow


Carsten supported Recurity Labs as a freelancer in fields of gray-box penetration testing and source code audits over several years. After his studies of computer science at the Freie Universität (FU) Berlin and gathering experience in consulting large companies, he joined the team in October 2009, providing skills in source code auditing and architectural reviews, ranging from embedded devices to globally deployed solutions.

Andreas Lindh


Andreas Lindh is a security consultant and researcher with over two decades of applied security experience and a wide variety of skills, spanning areas such as Web application security, network intrusion detection, Malware analysis and many more. Prior to joining Recurity Labs in 2015, Andreas worked for international telecoms and financial institutions, and a global automotive manufacturer, as well as for a managed security services provider. At Recurity Labs, his focus areas are source code audits, and application and device security assessments.

Andreas presented at leading industry conferences, such as Black Hat USA and Troopers, and is a member of the Black Hat review board.

Sascha Schirra


Sascha joined the consulting team in Juli 2018 after supporting Recurity Labs as a freelancer for several years. His focus areas are source code audits, mobile security reviews, embedded system analysis and reverse engineering. Sascha holds a title as state-certified technician for Informatics. Prior to joining Recurity Labs, he worked as a software developer and IT security specialist for a German state authority.

Stefan Seefeldt


Stefan Seefeldt is part of the consulting team at Recurity Labs since March 2018, focusing on source code audits and penetration testing, while also having a soft spot for design reviews and Threat/Attack Modeling . Stefan graduated with an M.S. in Computer Science and wrote his Master’s thesis on advanced exploitation techniques.

David Gullasch


David Gullasch studied Information Systems Technology at TU Dresden and started his career in the IT security industry in 2001. His background is on the one hand academic, covering areas like cryptography and Operating System architecture, and on the other very practical, including low-level hard- and software reverse-engineering and vulnerability research.

His published work includes academic papers in the area of micro architectural side-channel attacks and several public security advisories. Since 2011, he has been working as security consultant primarily in the sectors of financial, pharmaceutical and technology manufacturing industries with a diverse experience in advising customers by conducting security analysis of various kinds (e.g. cryptographic design reviews, source code audits, forensic analysis, automated Malware analysis, penetration testing of networks, embedded systems, mobile and Web applications). David joined the team in early 2019.

Micaela Ranea-Sánchez


With a substantial background in Computer Science and software development, Micaela joined Recurity Labs in September 2018. She entered the security consultancy arena after being an active contributor in the open source security community for a couple of years. Her main areas of focus are penetration testing and source code audits, while considerably contributing to our internal toolchain development.

Bruno Kirschner


Bruno joined Recurity Labs in January 2020 after spending three years as part of the Recurity Labs subsidiary P3KI, focusing on authorization solutions and software development. Since he finished his Master in Computer Science in 2016, he continued to keep in touch with his former university and gives lectures about IT security from time to time. Furthermore, he is a member of the examining board of the German “Chamber of Industry and Commerce” (IHK). Bruno’s current focus points are source code audits and penetration tests.

Johan Rydberg Möller


Johan is a security consultant with way over a decade of applied security experience spanning a variety of fields and industries. His focus has been - and still is - application security, where he tests, develops and secures all kinds of applications running on various platforms, from servers to cell phones, to embedded automotive devices and wearable tech. Prior to joining Recurity Labs in mid 2020, Johan was a co-founders of the Swedish security consultancy firm Assured, where he served as head of the penetration testing team, working in both a managerial and hands-on capacity. Work aside, Johan also has a private passion for IT security, manifested by engagements, such as running Security Fest (annual Swedish security conference), co-hosting Säkerhetspodcasten (Swedens longest running security podcast), and by regularly contributing to open security forums, such as OWASP.

John Robert Lißke


John joined the Consulting Team in early 2022. During and after serving in the federal defense area, he studied IT security at the Wilhelm Büchner Mobile University of Technology. There, and by investing a considerable amount of own time, he gained knowledge and experience, mainly in Web- and application penetration testing. In his current capacity as Junior Consultant, John is eager to deepen his skills and learn from the rest of the family.

Contracting Consultants

In addition to its own team, Recurity Labs works with a selected body of contracting consultants. This group consists of hand-picked professionals with exceptional skills in their specific area of expertise. Close cooperation with contracting consultants is one of the core operating concepts at Recurity Labs as such specialists often do not fit into permanent employments, since it steals the self-development time they need, want and require. On the other hand, permanent positions cannot constantly provide challenging missions. Recurity Labs strives to balance the two, achieving a high acceptance by the contracting consultants and full satisfaction by our customers, who get extra specialist knowledge with the standards and quality of Recurity Labs’ work.